In general, silos have been in use for many years. Typically, these silos have a series of vertically arrayed doors which open into the interior of the silo and discharge through an externally attached discharge chute. The farmer must serially open and close the doors and attach the silo unloader to each door frame in turn as the silo is emptied. This is time consuming, inefficient and requires a substantial amount of climbing, often at great heights in order to proceed with the unloading operation. None of the prior art silos disclose an integral discharge passage in the silo wall with a continuous vertical opening extending from top to bottom of the silo and which opening features no obstructions.